A seat slide device for a vehicle configured so that a position of a seat for a vehicle is adjustable in a front-rear direction of a vehicle has been conventionally known. A seat slide device for a vehicle described in Patent document 1 includes a lower rail, an upper rail mounted at the lower rail to be movable relative thereto, and an engagement member disposed within a void formed between the lower rail and the upper rail.
Specifically, as illustrated in FIG. 16, an engagement member 120 includes plural engagement protrusions 124 at an end so as to protrude in a width direction W. Engagement protrusion bores 149 are provided at two surfaces of an upper rail 130, two surfaces facing each other in the width direction W. In a case where the engagement member 120 is disposed within the upper rail 130, each of the engagement protrusions 124 passes through each of the engagement protrusion bores 149 so as to protrude from the upper rail 130 in the width direction W. Thus, tip ends of the engagement protrusions 124 are exposed to the outer side of the upper rail 130 so as to be engageable with a lower rail (not illustrated). The engagement member 120 includes a rotary shaft 128 which includes a substantially column configuration.
According to the seat slide device in Patent document 1, single upper rail is configured to be divided. Specifically, as illustrated in FIG. 16, the upper rail 130 is constituted by a first member 130a and a second member 130b. In order to assemble the engagement member 120 on the upper rail 130, first, the engagement member 120 is disposed between the first member 130a and the second member 130b in a state where the first member 130a and the second member 130b are separated from each other in the width direction W. Then, the first member 130a and the second member 130b are brought to come closer to each other so that the engagement protrusions 124 are inserted to the engagement protrusion bores 149 of the upper rail 130. In addition, the rotary shaft 128 of the engagement member 120 is also inserted to shaft bores 131 formed at the members 130a and 130b respectively. Then, the first and second members 130a and 130b are tightened to each other by a fastener such as a bolt and a nut, for example, which are not illustrated.
Because the upper rail 130 is configured to be divided in the width direction W, the engagement member 120 may be assembled on the upper rail 130 regardless of the length of each of the engagement protrusions 124 and the rotary shaft 128 in the width direction W.
In addition, the engagement member 120 is supported to be rotatable within the upper rail 130. The engagement protrusions 124 selectively engage with and disengage from lock bores (of which illustration is omitted) of the lower rail depending on a rotation position of the engagement member 120. Accordingly, the seat slide device for the vehicle may prohibit or permit the upper rail 130 to move relative to the lower rail which is fixed to a vehicle floor.
Further, Patent document 2, for example, discloses a construction where one support pin is inserted to a side wall of an upper rail and an engagement member so as to support the engagement member within the upper rail. Furthermore, Patent document 3, for example, discloses a construction where an operation lever is rotatably supported via a support pin and an engagement member is supported at an upper rail in a simple non-rotatable manner by a fitting protruding portion formed at the engagement member.